This group of antigens are directly accessible to circulating antibodies (considered pathogenic) due to their extracellular location (i.e. neuronal cell surface) and are responsive to treatment.
These antibodies are detected by the staining seen on the transfected HEK cells.
Some of these include the following:-
Non-paraneoplastic antibodies
Antibody | Antigen | Neurological Disorder | Associated tumour(s) | Target antigen |
NMDAR |
Glutamate receptor |
LE |
Ovarian teratoma |
N-terminal extracellular domain of the NR1 subunit of NMDAR |
LG1 |
VGKC protein |
LE with FBDS |
Rare |
LGI1 |
CASPR2 |
VGKC protein |
Neuromyotonia |
+ / - |
CASPR2 |
APAR |
Receptor |
LE |
+ / - Lung, breast or thymus |
GluR1 and GluR2 subunits of AMPAR |
GABABR |
Receptor |
LE (mainly seizures) |
SCLC |
B1 receptor subunit of GABABR |
Glycine |
Receptor |
PERM |
Rare |
α1 receptor subunit of Glycine receptor |
Abbreviations:
AMPAR - alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor, CASPR2 = contactin-associated protein-like 2, GABA – Gamma amino butyric acid, LGI1 = Leucine-rich glioma-inactivated protein 1 antibody, SOX = Sex determining region Y-box,
FBDS = Faciobrachial-dystonic seizures, LE = limbic encephalomyelitis, PERM = Progressive encephalomyelitis, with rigidity and myoclonus
VGKC = Voltage gated potassium channel,
HEK = Human Embryonic Kidney